Skutterudite var. Smalltite with Arsenopyrite, Niederschlema, Erzgebigkreis, Saxony, Germany VERY RARE
Smaltite is a variety of skutterudite, a rare mineral composed of cobalt and nickel arsenide. The species is historically significant as a source of cobalt for producing blue pigments like smalt, used in glass and porcelain. Originally considered to be a cobalt diarsenide, smaltite has been reclassified as an arsenic-deficient variety of skutterudite. It is quite rare worldwide. This specimen presents well-defined, metallic silver-grey, complexly interpenetrating cubo-octahedral masses with a sublime cobalt-blue sheen. I have also included close up photos of a secondary, matte-gray species, possibly smaltite-skutterudite as well, which – based upon relict morphology and habit - may be a pseudomorph after silver and/or a silver sulfide species, but this is conjecture (see, for example, Mindat specimen ID N38-9GU). This extremely rare specimen is sourced from the historically significant Schneeberg mining district, located in the Erzgebirgskreis region, Saxony, Germany, a mountainous area with numerous silver, cobalt and iron mines that have been mined since ancient times. The typewritten label likely dates from the 1970s.
